食品添加剂二氧化碳中氧标准物质重量制备方法及重量制备不确定度的研究

研究了食品添加剂二氧化碳中氧标准物质重量制备的实验方法及不确定度评价研究的内容.采用中国计量科学研究院设计加工的气体充填装置制备了二氧化碳中氧标准物质,该装置低压系统真空度达到7×10-3Pa;气体称量装置采用美国Mettler SB16001电子天平(16 kg、0.1 g)和上海第二天平仪器厂TG320B高精密天平...

Study on Preparation and Preparation Uncertainty of Oxygen in Carbon Dioxide Reference Materials as Food Additives by Gravimetric Method

This article introduced the preparation and uncertainty evaluation of oxygen in carbon dioxide reference materials as food additives by gravimetric method.The gas filling device was designed by National Institute of Metrology,and the vacuum degree of low pressure system can achieve 7×10-3 Pa;The quality of components and dilution gas was weighed by US Mettler SB16001 electronic balance(16 kg,0.1 g) and TG320B high precision balance(20 kg,10 mg) made by Shanghai Secondary Balance Instrument Factory.The uncertainty of weighing the quality of component gas(raw material gas) as follows: the uncertainty is less than 0.007 g when the quality of component gas is less than 50 g;the uncertainty is less than 0.010 g when the quality of component gas is in the range of 50～400 g.After evaluation,the expanded uncertainty of oxygen in carbon dioxide reference materials whose value is in the range of(10～30)×10-6 prepared by gravimetric method is less than 2%.